It has already been proposed in the field of bacteriology to provide such devices constituted by a circular housing in which a central cup is provided for receiving the sample of bacterial suspension and from which there leaves a plurality of radial channels forming calibrated pipettes, each of said channels leading, by way of a capillary constriction, into an optical cup containing a culture medium and an antibiotic which are lyophilized (freeze dried). Thus the central cup and the channels are filled statically (the volume in each channel being calibrated by means of an end constriction). A stopper then simultaneously isolates all the radial channels, then rapid spinning transfers the liquid from each channel towards its associated optical cup (the centrifuging enabling the liquid to pass through the constrictions). These devices, although very efficient, nevertheless have some limits if it is required to use them for conventional analysis of a sample of liquid and not for bacteriology: indeed, the smaller dimensions remain limited by the presence of the calibrated pipettes which are already very small and end in a constriction. Now on site analysis by means of a portable analysis device requires further miniaturisation, with a conditioning device whose housing could, for example, have a diameter of the order of 4 centimeters, such miniaturisation is difficult to produce and excessively expensive when calibrated radial pipettes are used.
The present invention aims to provide a conditioning device whose design permits the use of very much smaller dimensions than those of previous devices, while remaining simple and suitable for mass-production by conventional moulding means.
The present invention provides a device for conditioning a sample of liquid with a view to analysing it. The device comprises a plurality of calibrated peripheral cells having two parallel surfaces for an optical measurement and connected to a central receptacle receiving said sample. Each of said cells is intended to contain a reagent. The device further comprises for each cell, means for conveying the sample from the receptacle to said cell with a view to filling it completely by centrifuging and escape means for air contained in said cell to said receptacle. The conveying means comprises an inlet orifice in each cell, and the escape means comprises an orifice nearer to the axis of rotation than said inlet orifice and leading into said receptacle. Each orifice is of such a size as to retain the liquid contained in each cell after complete filling thereof.